Radiation-curable coating compositions, composite and plastic materials coated with said compositions and methods for their preparation

ABSTRACT

Curable coating composition suitable for use on composite substrates such as plastic composites, cementitious composites, ceramic composites, and engineered wood, or on plastic materials. The curable coating composition comprises a multifunctional oligomer, a monomer selected from the group consisting of monofunctional monomers, difunctional monomers and mixtures thereof, a photoinitiator, a polyester resin and a polycarboxylic acid. Also disclosed is a method of coating the substrates with the curable coating composition and a coated substrate wherein the cured coating resides on the surface of the substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority to and the benefit of U.S.Provisional Patent Application No. 60/968,990, filed Aug. 30, 2007, andU.S. Provisional Patent Application No. 60/914,224, filed Apr. 26, 2007,each of which is incorporated by reference.

BACKGROUND OF THE INVENTION

Composite substrates such as cementitious composites, plasticcomposites, ceramic composites, and engineered woods are well known.These materials are currently used in many construction andmanufacturing applications, for example, outdoor deck flooring,railings, fences, landscaping timbers, cladding and siding, parkbenches, molding and trim, window and door frames, and indoor furniture.

While coatings have been developed for application onto the exteriorsurface of these substrates, drawbacks remain. Thus, there exists a needfor improved: coating compositions suitable for application ontocomposite substrates; methods of preparing coated composite substrates;and coated composite substrates per se.

The invention provides improved coating compositions, coated substratesand methods for their preparation. The advantages of the invention, aswell as additional inventive features, will be apparent from thedescription of the invention provided herein.

BRIEF SUMMARY OF THE INVENTION

The foregoing and other needs are fulfilled by the present inventionwhich provides, in one aspect, a radiation curable coating compositionsuitable for application onto the surface of a variety of substrates,desirably the surface of composite substrates such as cementitiouscomposites, plastic composites, ceramic composites, plastic compositesand engineered woods, as well as the surface of plastics per se. Theradiation curable coating composition comprises a multifunctionaloligomer, a monomer selected from the group consisting of monofunctionalmonomers, difunctional monomers and mixtures thereof, a photoinitiator,a polyester resin and a polycarboxylic acid.

In another aspect, the invention provides a method for preparing acoated composite substrate comprising applying a radiation curablecoating composition onto the substrate and curing the coatingcomposition by exposing the curable coating to radiation, wherein thecurable coating composition comprises a multifunctional oligomer, amonomer selected from the group consisting of monofunctional monomers,difunctional monomers and mixtures thereof, a photoinitiator, apolyester resin and a polycarboxylic acid.

Yet another aspect of the present invention provides a coated compositesubstrate comprising the substrate and a radiation-cured coating on thesurface of the substrate, wherein the radiation-cured coating is formedby exposing to radiation a radiation-curable coating compositioncomprising a multifunctional oligomer, a monomer selected from the groupconsisting of monofunctional monomers, difunctional monomers andmixtures thereof, a photoinitiator, a polyester resin and apolycarboxylic acid.

DETAILED DESCRIPTION OF THE INVENTION

It has been discovered that radiation-curable coating compositionscomprising a multifunctional oligomer, a monomer selected from the groupconsisting of monofunctional monomers, difunctional monomers andmixtures thereof, a photoinitiator, a polyester resin and apolycarboxylic acid, provides performance advantages relative toexisting coatings, and is particularly useful when applied and cured oncertain substrates—composite substrates such as cementitious composites,plastic composites, ceramic composites, and engineered woods, as well ason plastics per se. For example, and among other benefits, the inventivecoating, after curing on a composite substrate such as a cementitiouscomposite, a plastic composite, a ceramic composite, a plasticcomposite, engineered wood or plastic, adheres well to these substrateseven after exposure of the coated material to a range of temperatures,moisture and sunlight; resists marring and abrasion; provides anaesthetically pleasing appearance; and is readily applied onto thematerial, and quickly cured, permitting its use in a high-speedmanufacturing environment.

Turning initially to the radiation-curable compositions of the presentinvention, the compositions comprise a multifunctional oligomer. Thisoligomer should be curable by radiation, and may desirably constitute,for example, an acrylate, and more desirably a urethane acrylate, suchas aliphatic and aromatic urethane acrylates, epoxy acrylates, melamineacrylates, polyester acrylates, polyether acrylates, silicone acrylates,dendritic acrylates, polybutadiene acrylates, amine acrylates, acrylicacrylates, amido and spiro ortho carbonate esters, and mixtures thereof.Aliphatic urethane acrylates are preferred, with trifunctional aliphaticpolyester urethane acrylate oligomers being most preferred. Illustrativeof aliphatic urethane acrylates suitable for use in the presentinvention include those marketed by Cytec Surface Specialties under thetrademark EBECRYL as 264, 265, 284N, 1290, 4866, 4883, 8210, 8301, 8402,8405, 5129 and 8411; those marketed by Sartomer as CN985B88, 964,944B85, 963B80, CN 929, CN 996, CN 968, CN 980, CN 981, CN 982B90, CN983, CN991; CN 2920, CN 2921, CN 9006, CN 9008, CN 9009, CN 9010;GENOMER 4302, 4312 and 4316 available from Rahn; Desmolux XP 2513 andVPLS 2265 available from Bayer Material Science Corporation; PHOTOMER6892 and 6008 available from Cognis; and NK OLIGO™ U24A and U-15HA™available from Kowa. Additional suppliers of aliphatic urethaneacrylates include the BR series of aliphatic urethane acrylates (forexample, BR 144 and 970) available from Bomar Specialties or the LAROMERseries of aliphatic urethane acrylates from BASF.

The multifunctional oligomer may be of any suitable molecular weight solong that it does not impart excessive viscosity to the coatingcomposition. This being said, the number average molecular weight maydesirably range from about 1,000 to about 10,000, preferably from about1,000 to about 8,000, more preferably from about 1,000 to about 5,000,and most preferably from about 1,200 to about 3,000.

The amount of the multifunctional oligomer in the curable compositionmay range from about 10% to about 80% by weight of the curablecomposition, but is desirably present at, for example, from about 15% toabout 60% by weight of the curable composition, preferably from about20% to about 55% by weight of the curable composition, and morepreferably from about 25% to about 50% by weight of the curablecomposition.

The curable coating compositions of the invention further comprise amonomer selected from the group consisting of monofunctional monomers,difunctional monomers and mixtures thereof. Any suitable monomer whichpossesses the aforementioned properties and which is radiation curablemay be used in the curable coating composition of the present invention.Examples of monomers suitable for inclusion in the curable compositionsinclude styrene, alpha-methylstyrene, substituted styrene, vinyl ester,vinyl ether, N-vinyl-2-pyrrolidone, (meth)acrylamide, N-substituted(meth)acrylamide, octyl(meth)acrylate, nonylphenolethoxylate(meth)acrylate, isononyl(meth)acrylate,isobomyl(meth)acrylate, 2-(2-ethoxyethoxy)ethyl(meth)acrylate,2-ethylhexyl(meth)acrylate, lauryl(meth)acrylate,beta-carboxyethyl(meth)acrylate, isobutyl(meth)acrylate, cycloaliphaticepoxide, alpha-epoxide, 2-hydroxyethyl(meth)acrylate,(meth)acrylonitrile, maleic anhydride, itaconic acid,isodecyl(meth)acrylate, dodecyl(meth)acrylate, n-butyl(meth)acrylate,methyl(meth)acrylate, hexyl(meth)acrylate, (meth)acrylic acid,N-vinylcaprolactam, N-vinylformamide, stearyl(meth)acrylate, hydroxyfunctional caprolactone ester(meth)acrylate, isooctyl(meth)acrylate,hydroxyethyl(meth)acrylate, hydroxymethyl(meth)acrylate,hydroxypropyl(meth)acrylate, hydroxyisopropyl(meth)acrylate,hydroxybutyl(meth)acrylate, hydroxyisobutyl(meth)acrylate,tetrahydrofurfuryl(meth)acrylate, ethylene glycol di(meth)acrylate,hexanediol di(meth)acrylate, triethylene glycol di(meth)acrylate,tetraethylene glycol di(meth)acrylate, dipropylene glycoldi(meth)acrylate, and alkoxylated polyol derived diacrylates, such aspropoxylated neopentyl glycol diacrylate, neopentyl glycoldi(meth)acrylate, and mixtures thereof (wherein “(meth)acrylate” refersto an acrylate and a methacrylate). Desirably, the monomers includeisobornyl acrylate, isodecyl acrylate, 1,6-hexanediol diacrylate, andmixtures thereof.

The monomer may be present in the curable composition in any suitableamount, for example, in an amount ranging from about 25% to about 75% byweight of the composition, preferably ranging from about 30% to about65% by weight of the composition, and more preferably from about 35% toabout 55% by weight of the composition.

The inventive curable coating compositions also comprise aphotoinitiator. Photointiators are well known in the art, and anyphotoinitiator capable of assisting in the cure of the curablecomposition may be used. Illustrative of suitable photoinitiators arephosphine oxides, ketones and their derivatives, benzophenones,carbocyanines and methines, polycyclic aromatic hydrocarbons, such asanthracene or the like, and dyestuffs, such as xanthenes, safranines andacridines. More generally, the photoinitiators may be chemicalsubstances belonging to one of the following major categories: compoundscontaining carbonyl groups, such as pentanedione, benzil, piperonal,benzoin and its halogenated derivatives, benzoin ethers, anthraquinoneand its derivatives, p,p′-dimethylaminobenzophene, benzophenone and thelike; compounds containing sulfur or selenium, such as the di- andpolysulfides, xanthogenates, mercaptans, dithiocarbamates, thioketones,beta-napthoselenazolines; peroxides; compounds containing nitrogen, suchas azonitriles, diazo compounds, diazides, acridine derivatives,phenazine, quinoxaline, quinazoline and oxime esters, for example,1-phenyl-1,2-propanedione 2-[0-(benzoyl)oxime]; halogenated compounds,such as halogenated ketones or aldehydes, methylaryl halides, sulfonylhalides or dihalides; phosphine oxides and photoinitiator dyestuffs,such as diazonium salts, azoxybenzenes and derivatives, rhodamines,eosines, fluoresceines, acriflavine or the like. Common photoinitiatorsinclude 2,2-diethoxyacetophenone, dimethoxyphenylaceto-phenone, phenylbenzoin, benzophenone, substituted benzophenones, phosphine oxides andthe like.

It is also possible to use mixtures of photoinitiators. For example,such mixtures may include combinations of camphorquinone; benzophenone;benzophenone derivatives (e.g.1-[4-(4-benzoyl-phenylsulfanyl)-phenyl]-2-methyl-2-(toluene-4-sulfonyl)-propan-1-one);acetophenone, acetophenone derivatives, for example,alpha-hydroxycycloalkyl phenyl ketones or dialkoxyacetophenones;alpha-hydroxy- or alpha-amino-acetophenones, for example,oligo-[2-hydroxy-2-methyl-1-[4-(1-methylvinyl)-phenyl]-propanone],2-hydroxy-2-methyl-1-phenyl-1-propanone,2-hydroxy-1-[4-(2-hydroxy-ethoxy)-phenyl]-2-methyl-propan-1-one,2-methyl-1-[4-(methylthio)phenyl]-2-(4-morpholinyl)-propan-1-one,2-dimethylamino-2-(4-methylbenzyl)-1-(4-morpholin-4-yl-phenyl)-butan-1-one,2-benzyl-2dimethylamimo-1-(3,4-dimethoxy-phenyl)-butan-1-one,2-benzyl-2-dimethylamino-1-(4-morpholin-4-yl-phenyl)-butan-1-one,2-methyl-1-(4-methylsulfanyl-phenyl)-2-morpholin-4-yl-propan-1-one;1-hydroxy-cyclohexylphenylketone; 4-aroyl-1,3-dioxolanes; benzoin alkylethers and benzil ketals, for example, benzil dimethyl ketal, phenylglyoxalates and derivatives thereof, for example, methylbenzoyl formate;dimeric phenyl glyoxalates, for example, oxo-phenyl-acetic acid2-[2-(2-oxo-2-phenyl-acetoxy)-ethoxy]-ethyl ester; peresters, forexample, benzophenone-tetracarboxylic acid perestels, as described, forexample, in U.S. Pat. Nos. 4,777,191 and 4,970,244; monoacylphosphineoxides, for example, (2,4,6-trimethylbenzoyl)-diphenyl-phosphine oxideor phenyl-(2,4,6-trimethylbenzoyl)-phosphinic acid ethyl ester,bisacylphosphine oxides, for example,bis(2,6-dimethoxybenzoyl)-(2,4,4-trimethyl-pent-1-yl)phosphine oxide,phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide orbis(2,4,6-trimethylbenzoyl)-(2,4-dipentoxyphenyl)phosphime oxide,trisacylphosphine oxides; halomethyltriazines, for example,2-[2-(4-methoxy-phenyl)-vinyl]-4,6-bis-trichloromethyl-[1,3,5]triazine,2-(4-methoxy-phenyl)-4,6-bis-trichloromethyl-[1,3,5]triazine,2-(3,4-dimethoxy-phenyl)-4,6-bis-trichloromethyl-[1,3,5]triazine,2-methyl-4,6-bis-trichloromethyl-[1,3,5]triazine;hexaarylbisimidazole/coinitiator systems, for example,ortho-chlorohexaphenyl-bisimidazole together with2-mercaptobenzthiazole; ferrocenium compounds or titanocenes, forexample, dicyclopentadienyl bis(2,6-difluoro-3-pyrrolo-phenyl)titanium;and borate photinitiators or O-acyloxime photoinitiators as described,for example, in U.S. Pat. No. 6,596,445. Preferred photoinitiatorsinclude phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,1-hydroxy-cyclohexylphenylketone,2-hydroxy-2-methyl-1-phenyl-1-propanone, phosphine derivatives, andmixtures thereof, with a combination ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide and1-hydroxy-cyclohexylphenylketone being more preferred when using UVpulse light technology, as described herein

Without being bound to any particular theory, it is believed that threecomponents of the inventive uncured composition—the photoinitiator,polyester resin and polycarboxylic acid—influence the adhesion of thecoating on the substrate after curing. More specifically, it was foundthat the photoinitiator, while necessary for effective curing, adverselyaffects curing when present at relatively high levels. It was furtherfound that, while the polyester resin and polycarboxylic acid assist inproviding satisfactory adhesion, the level of the polyester resin isdesirably controlled because this component also adversely affectsadhesion of the cured coating when included at relatively high levels.Thus, it is advantageous to include both the polyester resin andpolycarboxylic acid to enhance the adhesion of the cured coating to thevarious composite substrates, while limiting the amounts ofphotoinitiator and polyester resin in the curable coating as describedin the following paragraphs in order to optimize the adhesion of thecured coating to these substrates.

Turing initially to the photoinitiator, while this component may beincluded in the curable composition in a widely varying amount, theamount of this component is desirably limited to that which assists inproviding adequate curing of the coating, but which does not adverselyaffect the adhesion of the cured coating to the substrate. Preferably,the amount of photoinitiator in the curable composition ranges fromabout 0.001% to about 10% by weight, more preferably from about 0.05% toabout 6% by weight, and most preferably from about 0.1% to about 5% byweight of the uncured composition.

A polyester resin is another component of the curable coatingcomposition. Examples of resins suitable for inclusion in thecomposition are Co-Resin 02-819/M22 available from Rahn and UVP6000-TP20available from Polymer Technologies Ltd.

The polyester resin may also be included in the curable composition invarying amounts, but is desirably limited to that which does notadversely affect the adhesion of the cured coating onto the substrate.Preferably, the amount of this resin may range from about 1% to about20% by weight, more preferably from about 1% to about 15% by weight, andmost preferably from about 1% to about 10% by weight of the curablecomposition

A polycarboxylic acid is a further component of the curable composition.While polycarboxylic acids suitable for use in the inventivecompositions include, for example, BYK-P-104 available from BYK Chemieand EFKA5006 available from Ciba Specialty Chemicals, it is preferredthat the acid be unsaturated. Without being bound to any particulartheory, it is believed that the unsaturated polycarboxylic acid, uponcuring, will become polymerized with other components of the curablecomposition, thereby providing the cured composition with enhancedadhesion due to the presence of the acid functionality within the curedcoating.

The polycarboxylic acid may be included in the curable composition inany amount suitable to provide the desired properties in the curedcoating, e.g., adhesion. In this regard, the amount of polycarboxylicacid may range broadly, but desirably ranges from about 0.01% to about10% by weight, more preferably from about 0.01% to about 5% by weight,and most preferably from about 0.01% to about 3% by weight of theuncured composition.

In a related aspect of the invention, the curable coating composition isnon-aqueous, and is desirably substantially free of an organic solvent.If present, the organic solvent is desirably limited to between about0.001% by weight to about 5% by weight, more desirably about 0.001% byweight to about 2% by weight, and preferably about 0.001% by weight toabout 1% by weight of the uncured composition. Most preferably, thecomposition should have less than about 1% by weight organic solvent inthe uncured composition.

The curable coating composition of the invention may further include oneor more supplemental adhesion promoters which, as its name implies, arebelieved to enhance the adhesion of the cured coating to the substrate,and in particular to the preferred substrates—cementitious composites,plastic composites, ceramic composites, and engineered woods. Thesupplemental adhesion promoter may be present in any suitable amount,but is desirably present from about 0.1% to about 20% by weight,preferably from about 0.1% to about 18% by weight, and more preferablyfrom about 0.5% to about 16% by weight of the uncured composition.Illustrative supplemental adhesion promoters include: phosphoric acidesters, e.g., Genorad 40 available from Rahn, Etermer 39 available fromEternal Chemical Co., Ebecryl 168 and 171 available from Cytec SurfaceSpecialties, and Sartomer CD-9050, CD-9051, and CD-9053 available fromSartomer; acrylic or acrylic acrylate resins, e.g., methyl methacrylateand n-butyl methacrylate sold as Degalan LP 64/12 and available fromDegussa Co.; acrylic acrylate sold as Lumicryl 1908, JR5-209, JR5-219,JR5-243 available from Estron Chemical, Inc.; acrylic acrylate sold asEbecryl 745, Ebecryl 1710 from Cytec Surface Specialties; and mixturesthereof.

A mixture of supplemental adhesion promoters may be used when enhancedadhesion of the cured coatings is desired. For example, the inclusion ofacrylic or acrylic acrylate resins in such a mixture has been found toenhance adhesion of the cured coatings without unduly increasing theviscosity of the uncured coating compositions.

As a means of enhancing the aesthetic qualities of the coating, and thusof the substrate, the curable coating composition may, if desired,include a colorant. Any suitable colorant may be employed, such as apigment, a dye or a combination thereof. The colorant may be present inany amount suitable to impart the desired coloration to the curedcoating, and preferably ranges from about 0.1% to about 10% by weight,more preferably from about 1% to about 8% by weight, and most preferablyfrom about 1% to about 5% by weight of the curable composition.

If used, suitable pigments include, but are not limited to, inorganicpigments such as titanium dioxide, zinc white, zinc sulfide, lithopones,carbon black, iron manganese black, spinel black, chromium oxide,chromium oxide hydrate green, cobalt green, ultramarine green, cobaltblue, ultramarine blue, manganese blue, ultramarine violet, cobaltviolet, manganese violet, red iron oxide, cadmium sulfoselenide,molybdate red, ultramarine red, brown iron oxide, mixed brown, spinelphases, corundum phases, chrome orange, yellow iron oxide, nickeltitanium yellow, chrome titanium yellow, cadmium sulfide, cadmium zincsulfide, chrome yellow, bismuth vanadate, iron oxide, diiron oxide, ironoxide hydrate, and mixtures thereof. Organic pigments may also be used,either alone or in combination with another type of colorant. Examplesof suitable organic color pigments include, but are not limited to,monoazo pigments, diazo pigments, anthraquinone pigments, benzimidazolepigments, quinacridone pigments, quinophthalone pigments,diketopyrrolovyrrole pigments, dioxazine pigments, indanthrone pigments,isoindoline pigments, isoindolinone pigments, azomethine pigments,thioindigo pigments, metal complex pigments, perinone pigments, perylenepigments, phthalocyanine pigments or aniline black. Preferred pigmentsare the inorganic pigments, with titanium dioxide, yellow iron oxide,red iron oxide and mixtures thereof being preferred. Illustrative oftransparent pigments suitable for use in the present invention includethose marketed by BASF as SICOTRANS® Yellow L 1916 and SICOTRANS® Red L2715 D.

Additionally, it was found that pigmented coatings may provide thecoated substrate with one or more desirable properties other thanenhanced appearance (coloration), such as improved weatherability,adhesion, and gloss retention. For example, it was found that theinclusion of inorganic pigments, such as the oxides, provided the curedcoating with enhanced resistance to sun exposure (e.g., blistering,peeling and the like), especially when the coating is applied ontocertain wood-containing composites. When included in compositions forexterior applications, it is preferred that exterior grade oxides andtransparent oxides be included in the coatings.

The coating compositions may also include one or more aesthetic agentswhich provide the cured coating with the desired finish. For example,certain agents will function to reduce the gloss of the cured coatingcomposition (gloss reducing agents), while others may be used to reducethe increase the slip-resistance of the cured coating or impart astucco-like finish thereto. While any material which functions to impartone or more of the foregoing properties to the cured coating compositionmay be used, silica sand, quartz grit, silica, talc, and micronizedsilica gel are desired, with silica, talc or micronized silica gel beingpreferably used when gloss reduction is desired.

While the aesthetic agent may be present in any amount desired such thatthe properties described herein are attained, the amount of the agentmay desirably range from about 0.1% to about 30% by weight, preferablyfrom about 1% to about 25% by weight, and more preferably from about 10%to about 20% by weight, all based on the weight of the curablecomposition. One skilled in the art upon reading this disclosure alsowould be readily able to determine the appropriate size of theparticulates which constitute the agent. Desirably, the silica sand mayrange from about 20 to about 100 mesh, and more preferably from about 30to about 50 mesh, while the quartz grit used is desirably about no. 3quartz grit.

When an aesthetic agent and/or pigment is included in the curablecomposition, it is preferred to include a relatively lower amount of theoligomer, and include both a monofunctional and a difunctional monomer,in the curable composition. In this respect, and by way of example, apreferred curable composition containing a gloss reducing agent maycomprise about 15% to about 40% by weight of a multifunctional oligomer,about 30% to about 70% by weight of a monomer, about 0.001% to about 4%by weight of a photoinitiator, about 1% to about 10% by weight of apolyester resin, and about 0.1% to about 5% by weight of apolycarboxylic acid, wherein the monofunctional monomer constitutes atleast about 50% by weight, more preferably at least about 70% by weight,and most preferably at least about 80% by weight of the total weight ofthe monomers included in the curable composition. The agent (e.g., glossreducing agent) may desirably be present in an amount ranging from about0.1% to about 30% by weight, preferably from about 1% to about 25% byweight, and most preferably from about 3% to about 20% by weight of thecurable composition, while the pigment may be present in an amountranging from about 0.1% to about 15% by weight, preferably from about 1%to about 10% by weight, and most preferably from about 2% to about 6% byweight of the curable composition.

In preferred curable compositions as described herein wherein anaesthetic agent (e.g., gloss reducing agent) is included in the absenceof a pigment, the aforesaid reduction in oligomer content may be used,with the weight ratio of monofunctional to difunctional monomer rangingfrom about 1:1 to about 5:1, and preferably from about 3:1 to about 4:1.Conversely, in preferred curable compositions as described hereinwherein a pigment is included with an aesthetic agent (e.g., glossreducing agent), the aforesaid reduction in oligomer content may beused, with the weight ratio of monofunctional to multifunctional (e.g.,difunctional) monomer ranging from about 20:1 to about 5:1, andpreferably from about 15:1 to about 10:1.

The thickness of the cured coating is desirably controlled to providethe properties desired in the finished product. Typically, the coatingswill have an average thickness of about 0.1 mil to about 20 mils,however coatings that exceed these typical ranges may be used dependingon the desired finished product.

The inventive curable compositions, after application onto a substrate,e.g., a cementitious composite, a plastic composite, a ceramiccomposite, engineered wood, or plastic, are cured by exposure to actinicradiation, preferably ultraviolet (UV) radiation or pulsed UV radiation,the latter desirably used when temperature-sensitive substrates areused, e.g., certain plastics (e.g., PVC) and plastic composites (e.g.,PVC composites). UV curing is well known to those skilled in the art,including determining the wavelength of radiation and exposure timesuitable for curing. UV curing may be effected by using one, two orthree UV lamps of different wavelengths, with the number of lampsincreasing as the thickness of the uncured coating increases.Illustrative of lamps that may be used include mercury lamps, galliumdoped lamps, iron doped lamps, pulsed UV radiation, and combinationsthereof.

The composite substrates referred to herein are well known to thoseskilled in the art, and are generally used in the construction industryand in the production of furniture, among other uses. The preferredcomposites are generally described as cementitious composites, plasticcomposites, ceramic composites, and engineered woods, although thecomposites used in the present invention should not be limited to thesespecific examples.

The structure of the aforementioned composite substrates are well knownto those skilled in the art, and are generally prepared using two ormore different materials that remain separate and distinct on amacroscopic level. The composite substrates may be thought of ascomprising two categories of constituent materials, a matrix andreinforcement and/or filler materials. Matrix materials include, forexample, bitumen, cements, polymers (e.g., PVC), metals and ceramics.Reinforcement and/or filler materials include, for example, aggregate,sand, crushed stone, ground minerals, calcium carbonate, calciumsulfate, aluminum trihydrate, talc, cellulosics (e.g., pond sludge, woodflour, sawdust, newspapers, alfalfa, wood pulp, wood chips, wood fibers,paper, cardboard and straw), steel reinforcing bars, glass fibers,C-glass, E-glass, S-glass, quartz, polymer fibers, nylon based polymerfibers, aramid fibers, polyethylene based polymer fibers, naturalfibers, hemp fibers, sisal fibers, carbon fibers, rayon based carbonfibers, polyacrylonitrile-based carbon fibers, pitch-based carbonfibers, ceramic fibers, alumina silica mixtures, silicon carbide, boron,textiles, felts, woven fabrics, plain weave fabrics, twill weavefabrics, satin weave fabrics, and stitched construction fabrics.

By way of example, a cementious composite may generally comprise amatrix comprising a cementitious material, an aggregate material and oneor more reinforcement and/or filler materials incorporated therein.Generally, the cementitious material (e.g., Portland cement, highalumina cement, lime, high phosphate cement, ground granulated blastfurnace slag cement and mixtures thereof) may comprise at least about10% to about 80% by weight of the composite substrate, preferably atleast about 20% by weight of the substrate, and more preferably at leastabout 25% by weight of the substrate. The reinforcement and/or fillermaterials include aggregate materials such as, for example, includesilica-based materials, desirably ground silica sand, but may also beamorphous silica, diatomaceous earth, coal combustion fly and bottomash, rice hull ash, blast furnace slag, granulated slag, steel slag,mineral oxides, mineral hydroxides, clays, dolomite, metal oxides andhydroxides, polymeric beads, cellulosics, polymer fibers and mixturesthereof. An illustrative cementitious composite may comprise from about10% to about 80% by weight cement, about 20% to about 80% by weightaggregate (e.g., silica) and about 0.5% to about 20% by weight of anon-aggregate fibrous material, e.g., cellulosic or polymer fibers. Afurther example comprises about 20% to about 50% by weight cement, about30% to about 60% by weight aggregate (e.g., silica) and about 0.5% toabout 15% by weight fibers. Examples of cementitious composites areprovided in U.S. Published Patent Application 2005/0235883A1.

A plastic composite may generally comprise a matrix comprising a plasticmaterial and one or more reinforcement materials. Generally, the plasticmaterial may comprise at least about 15% by weight of the substrate,preferably at least about 20% by weight of the substrate, and morepreferably at least about 25% by weight of the substrate. Morepreferably, the plastic may comprise from about 30% to about 60% byweight of the composite.

The term plastic or plastic material as used in connection with thesubstrates described herein (a plastic composite substrate or plasticsubstrate, the latter being further described below) is understood bythose skilled in the art, and may include a wide variety of polymericmaterials such as polyethylene (e.g., low-density (LDPE) andhigh-density polyethylene (HDPE)), polypropylene (PP), polystyrene (PS),acrylonitrile butadiene styrene (ABS), poly(polyethylene terephthalate),polyester, polyamides, polyvinyl chloride (PVC), polyurethane,polycarbonate, poly(vinyldiene chloride), poly(methyl methacrylate),polytetrafluoroethylene, polyetheretherketone, polyetherimide,phenolics, phenol formaldehyde, urea formaldehyde, melamineformaldehyde, melamine formaldehyde, polylactic acid, plastarch materialand mixtures thereof. In plastic composites, PVC, ABS, PP, HDPE and PSare preferred plastic materials, with cellulosics (most desirably woodproducts such as wood flour) being the preferred reinforcement material.An illustrative plastic composite is described in U.S. Published PatentApplication 2004/0147625.

A plastic composite wherein polyvinyl chloride (PVC) is the plasticmaterial (which may be referred to as a PVC composite) included thereinmay generally comprise a matrix comprising PVC, wherein the PVC isdesirably present in the composite from about 50 to about 95 wt. %, moredesirably from about 70 wt. % to about 90 wt. %, and most desirably fromabout 80 wt. % to about 90 wt. %; a plasticizer, wherein the plasticizeris desirably present in the composite from about 0.1 to about 20 wt. %,more desirably from about 1 wt. % to about 10 wt. %, and most desirablyfrom about 1 wt. % to about 5 wt. %; and one or more reinforcingmaterials (e.g., fillers), wherein the reinforcing material is desirablypresent in the composite from about 0.1 to about 20 wt. %, moredesirably from about 1 wt. % to about 15 wt. %, and most desirably fromabout 2 to about 10 wt. %.

Plasticizers suitable for use in the PVC composite are known in the artand include phthalates, and desirably alkyl phthalates such asdiisodecyl phthalate. Epoxidized soybean oil may also be used as aplasticizer.

Fillers suitable for inclusion in the PVC composite are also known inthe art and include, but are not limited to, calcium carbonate, clays,silicate and talc. Other optional components include colorants, flameretardants and stabilizers. Generally, it is desired that the PVCcomposite be colored, preferably white. Colorants suitable for impartinga white color to the PVC composite include titanium dioxide, withoptical brighteners also being added to enhance appearance.

The PVC composite may be in any form, but is preferably extruded priorto application of the curable coatings described herein onto thecomposite.

A ceramic composite may generally comprise a matrix comprising ceramicmaterial and one or more reinforcement materials. Generally, the ceramicmaterial may comprise at least about 15% by weight of the substrate,preferably at least about 20% by weight of the substrate, and morepreferably at least about 25% by weight of the substrate.

Engineered wood may generally comprise a matrix comprising wood and oneor more reinforcement materials, the latter desirably constituting oneor more organic materials, e.g., flax, corn stover, natural fibers,bamboo, and other materials that would readily be understood as such.Generally, wood may comprise at least about 15% by weight of thesubstrate, preferably at least about 20% by weight of the substrate, andmore preferably at least about 25% by weight of the substrate.

The curable coating compositions of the present invention also may beused to coat plastic substrates. Generally, the plastic material (asdescribed above) may comprise more than least about 99% by weight of theplastic substrate. Most preferably, the plastic substrate will besubstantially free of material that is not plastic. The coatings findparticular use in coating PVC plastic substrates.

The present invention also provides methods for preparing a coatedcomposite substrate or coated plastic substrate and the resulting coatedsubstrate per se. The inventive method for preparing the coatedcomposite substrate or coated plastic substrate comprises applying aradiation curable coating composition as described herein onto acomposite substrate or plastic substrate as described herein, and curingthe coating composition by exposing the curable coating to radiation.The coated composite substrate or coated plastic substrate comprises thecomposite or plastic substrate as described herein and a radiation-curedcoating on the surface of the substrate as described herein.

Preferably, and as will be appreciated by those skilled in the art, thecurable coating may be applied directly onto the surface of thecomposite or plastic substrate by any suitable means, including but notlimited to, brushes, rollers, spray devices, vacuum coaters and thelike. Moreover, the curable coating may be applied onto the surface ofthe composite substrate or plastic substrate in the absence of a primer.This provides further efficiencies by eliminating the need for anadditional component and processing step. This being said, the presentinvention does not exclude the use of a primer or priming method (e.g.,fluoroxidation, heat, corona, and plasma priming) on a composite orplastic substrate prior to application of the curable coatingcomposition thereon.

The properties of the curable coatings described herein may be tested inaccordance with methods published by the American Society For TestingAnd Materials (ASTM) and Japanese Industrial Standards (JIS), anddesirably meets at least one and more desirably a plurality of thesetest standards. The adhesion of the cured coating to the substratesdisclosed herein may be measured using ASTM 3359, ASTM D 6944-03 MethodB, ASTM D 4585, ASTM D 6943-03, ASTM G-154, ASTM D5402, ASTM D3023, ASTMD3273, ASTM D3274, and JIS Z 2801:2000. Desirably, and under ASTM 3359,the cured coating composition will have an adhesion value when appliedand cured on a substrate of at least 4B (80%), and preferably 5B (100%),and will preferably retain this value after 96 hours at 20°F.-25° F.,and will more preferably retain this value after 144 hours at 120° F.Preferably, and under a test similar to ASTM D 6944-03 Method B (25cycles of 8 hours of freezing followed by 16 hours of heating), thecured coating composition will have an adhesion value when applied andcured on a substrate of at least 4B, and preferably 5B. Preferably, andunder ASTM D 4585 (1000 hours), the cured coating composition will showno effects from the test and will have a gloss retention of 95% and a ΔE(CIELAB) of about 1.5 units. Preferably, and under ASTM D 6943-03(immersion test using water for 30 days), the cured coating compositionwill show no visual change and will have an adhesion value when appliedand cured on a substrate of at least 4B, and preferably 5B. Preferablyand under a test similar to ASTM G-154 (QUV Weather Test, consisting ofa 1000 hours of the following cycles: 12 hours of UV light at awavelength of 340 nm, followed by 11 hours and ten minutes ofcondensation, followed by ten minutes of water spray), the cured coatingcomposition will have a gloss retention (60° meter) of at least about70%, preferably at least about 80%, and more preferably at least about90%, and color change measured as ΔE (CIELAB) of less than about 5units, preferably less than about 3 units, and more preferably less thanabout 2 units. Preferably, and under ASTM D5402 (solvent resistance testusing MEK with 100 double rubs), the cured coating composition will showno effect from the test. Preferably, and under ASTM D3023 (stainresistance test using mustard, ketchup, barbeque sauce, red wine,relish, and magic marker as stain compounds for 24 hours and cleanedwith soap and water), the stain compounds are easily cleaned with noeffect on the cured coating composition. Preferably, and under ASTMD3273 and ASTM D3274 (mold growth resistance test conducted for 28 days)the cured coating will show mold growth of at least about 8 (per ASTMD3274), preferably mold growth of at least about 9, and more preferablymold growth of about 10 (no discernable growth). Preferably, and underJIS Z 2801:2000 (antimicrobial activity test using S. aureus, E. coli,and K. pneumonae) the cured coating composition will show a reduction ofantimicrobial activity of at least about 90%, preferably a reduction ofantimicrobial activity of at least about 95%, and more preferably areduction of antimicrobial activity of at least about 99%.

All references, including publications, patent applications, andpatents, cited herein are hereby incorporated by reference to the sameextent as if each reference were individually and specifically indicatedto be incorporated by reference and were set forth in its entiretyherein.

The use of the terms “a” and “an” and “the” and similar referents in thecontext of describing the invention (especially in the context of thefollowing claims) are to be construed to cover both the singular and theplural, unless otherwise indicated herein or clearly contradicted bycontext. The terms “comprising,” “having,” “including,” and “containing”are to be construed as open-ended terms (i.e., meaning “including, butnot limited to,”) unless otherwise noted. Recitation of ranges of valuesherein are merely intended to serve as a shorthand method of referringindividually to each separate value falling within the range, unlessotherwise indicated herein, and each separate value is incorporated intothe specification as if it were individually recited herein. All methodsdescribed herein can be performed in any suitable order unless otherwiseindicated herein or otherwise clearly contradicted by context. The useof any and all examples, or exemplary language (e.g., “such as”)provided herein, is intended merely to better illuminate the inventionand does not pose a limitation on the scope of the invention unlessotherwise claimed. No language in the specification should be construedas indicating any non-claimed element as essential to the practice ofthe invention.

Preferred embodiments of this invention are described herein, includingthe best mode known to the inventors for carrying out the invention.Variations of those preferred embodiments may become apparent to thoseof ordinary skill in the art upon reading the foregoing description. Theinventors expect skilled artisans to employ such variations asappropriate, and the inventors intend for the invention to be practicedotherwise than as specifically described herein. Accordingly, thisinvention includes all modifications and equivalents of the subjectmatter recited in the claims appended hereto as permitted by applicablelaw. Moreover, any combination of the above-described elements in allpossible variations thereof is encompassed by the invention unlessotherwise indicated herein or otherwise clearly contradicted by context.

1. A curable coating composition comprising a multifunctional oligomer,a monomer selected from the group consisting of monofunctional monomers,difunctional monomers and mixtures thereof, a photoinitiator, apolyester resin and a polycarboxylic acid.
 2. The curable coatingcomposition of claim 1, wherein the multifunctional oligomer comprisesabout 10% to about 80% by weight of the composition, the monomercomprises about 25% to about 75% by weight of the composition, thephotoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 20% byweight of the composition, and the polycarboxylic acid comprises about0.01% to about 10% by weight of the composition.
 3. The curable coatingcomposition of claim 1, wherein the composition is substantially free oforganic solvent.
 4. The curable coating composition of claim 2 furthercomprising a supplemental adhesion promoter, and wherein themultifunctional oligomer comprises about 15% to about 60% by weight ofthe composition, the monomer comprises about 30% to about 65% by weightof the composition, the photoinitiator comprises 0.001% to about 6% byweight of the composition, the polyester resin comprises about 1% toabout 15% by weight of the composition, the polycarboxylic acidcomprises about 0.01% to about 5% by weight of the composition, and thesupplemental adhesion promoter comprises about 0.1% to about 20% byweight of the composition.
 5. The curable coating composition of claim1, wherein the multifunctional oligomer is a trifunctional aliphaticpolyester urethane acrylate oligomer and has a molecular weight of fromabout 1,200 to about 3,000.
 6. The curable coating composition of claim5, wherein the monomer is selected from the group consisting ofisobornyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate, andmixtures thereof.
 7. The curable coating composition of claim 6, whereinthe photoinitiator is selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives, and mixturesthereof.
 8. The curable coating composition of claim 4, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobornyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, and the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof. 9.The curable coating composition of claim 4, wherein the multifunctionaloligomer comprises about 20% to about 55% by weight of the composition,the monomer comprises about 30% to about 55% by weight of thecomposition, the photoinitiator comprises 0.001% to about 6% by weightof the composition, the polyester resin comprises about 1% to about 10%by weight of the composition, the polycarboxylic acid comprises about0.01% to about 3% by weight of the composition, and the supplementaladhesion promoter comprises about 0.1% to about 20% by weight of thecomposition, and wherein the monomer comprises at least about 50% byweight of a monofunctional monomer.
 10. The curable coating compositionof claim 9, wherein the multifunctional oligomer comprises atrifunctional aliphatic polyester urethane acrylate oligomer and has amolecular weight from about 1,200 to about 3,000, the monomer isselected from the group consisting of isobornyl acrylate, isodecylacrylate, 1,6 hexanediol diacrylate and mixtures thereof, thephotoinitiator is selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives, and mixturesthereof, and the supplemental adhesion promoter is selected from thegroup consisting of a phosphoric acid ester, an acrylic, and acrylicacrylate, and mixtures thereof.
 11. The curable coating composition ofclaim 1 further comprising a colorant.
 12. The curable coatingcomposition of claim 11, wherein the multifunctional oligomer comprisesabout 15% to about 60% by weight of the composition, the monomercomprises about 30% to about 65% by weight of the composition, thephotoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 10% byweight of the composition, and the polycarboxylic acid comprises about0.01% to about 5% by weight of the composition.
 13. The curable coatingcomposition of claim 11, wherein the colorant is a pigment, the curablecoating comprises a monofunctional monomer and a difunctional monomer,and wherein the weight ratio of the monofunctional monomer to thedifunctional monomer ranges from about 1:1 to about 5:1.
 14. The curablecoating composition of claim 12 further comprising an adhesion promoter,wherein the multifunctional oligomer comprises a trifunctional aliphaticpolyester urethane acrylate oligomer and has a molecular weight fromabout 1,200 to about 3,000, the monomer is selected from the groupconsisting of isobornyl acrylate, isodecyl acrylate, 1,6 hexanedioldiacrylate and mixtures thereof, the photoinitiator is selected from thegroup consisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof, andthe colorant is a pigment.
 15. The curable coating composition of claim14, wherein the multifunctional oligomer comprises about 40% to about60% by weight of the composition, the monomer comprises about 35% toabout 55% by weight of the composition, the photoinitiator comprises0.001% to about 4% by weight of the composition, the polyester resincomprises about 1% to about 10% by weight of the composition, thepolycarboxylic acid comprises about 0.01% to about 3% by weight of thecomposition, the supplemental adhesion promoter comprises about 0.1% toabout 3% by weight of the composition, and the pigment comprises about0.1% to about 10% by weight of the composition, and wherein the monomercomprises at least about 50% by weight of a monofunctional monomer. 16.The curable coating composition of claim 1 further comprising anaesthetic agent.
 17. The curable coating composition of claim 16,wherein the multifunctional oligomer comprises about 15% to about 50% byweight of the composition, the monomer comprises about 30% to about 70%by weight of the composition, the photoinitiator comprises 0.001% toabout 6% by weight of the composition, the polyester resin comprisesabout 1% to about 10% by weight of the composition, the polycarboxylicacid comprises about 0.01% to about 5% by weight of the composition, andthe aesthetic agent comprises about 0.1% to about 30% by weight of thecomposition.
 18. The curable coating composition of claim 16, whereinthe curable coating comprises a monofunctional monomer and adifunctional monomer, and wherein the weight ratio of the monofunctionalmonomer to the difunctional monomer ranges from about 20:1 to about 5:1.19. The curable coating composition of claim 17 further comprising asupplemental adhesion promoter, wherein the multifunctional oligomercomprises a trifunctional aliphatic polyester urethane acrylate oligomerand has a molecular weight from about 1,200 to about 3,000, the monomeris selected from the group consisting of isobomyl acrylate, isodecylacrylate, 1,6hexanediol diacrylate and mixtures thereof, thephotoinitiator is selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic acrylate, and mixtures thereof, and the aestheticagent is a gloss reducing agent selected from the group consisting ofsilica sand, silica, talc and mixtures thereof.
 20. The curable coatingcomposition of claim 19, wherein the multifunctional oligomer comprisesabout 20% to about 30% by weight of the composition, the monomercomprises about 50% to about 60% by weight of the composition, thephotoinitiator comprises 0.001% to about 4% by weight of thecomposition, the polyester resin comprises about 1% to about 10% byweight of the composition, the polycarboxylic acid comprises about 0.01%to about 3% by weight of the composition, the supplemental adhesionpromoter comprises about 0.1% to about 3% by weight of the composition,and the aesthetic agent comprises about 0.1% to about 25% by weight ofthe composition.
 21. The curable coating composition of claim 16 furthercomprising a colorant.
 22. The curable coating composition of claim 21,wherein the multifunctional oligomer comprises about 15% to about 50% byweight of the composition, the monomer comprises about 30% to about 60%by weight of the composition, the photoinitiator comprises 0.001% toabout 6% by weight of the composition, the polyester resin comprisesabout 1% to about 10% by weight of the composition, the polycarboxylicacid comprises about 0.01% to about 5% by weight of the composition, theaesthetic agent comprises about 0.1% to about 30% by weight of thecomposition, and the colorant comprises about 0.1% to about 15% byweight of the composition.
 23. The curable coating composition of claim22 further comprising a supplemental adhesion promoter, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobomyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof, theaesthetic agent is selected from the group consisting of silica sand,quartz grit, silica, talc and mixtures thereof, and the colorantcomprises a pigment.
 24. The curable coating composition of claim 23,wherein the multifunctional oligomer comprises about 20% to about 30% byweight of the composition, the monomer comprises about 30% to about 45%by weight of the composition, the photoinitiator comprises 0.001% toabout 6% by weight of the composition, the polyester resin comprisesabout 1% to about 10% by weight of the composition, the polycarboxylicacid comprises about 0.01% to about 3% by weight of the composition, thesupplemental adhesion promoter comprises about 0.1% to about 20% byweight of the composition, the aesthetic agent comprises about 0.1% toabout 20% by weight of the composition and the pigment comprises about0.1% to about 5% by weight of the composition.
 25. The curable coatingcomposition of claim 1, wherein the composition comprises no more thanabout 5% by weight of an organic solvent.
 26. The curable coatingcomposition of claim 25, wherein the composition comprises no more thanabout 1% by weight of an organic solvent.
 27. A method for providing asubstrate with a cured coating comprising applying a curable coatingcomposition onto a composite substrate and curing the coatingcomposition, wherein the curable coating composition comprises amultifunctional oligomer, a monomer selected from the group consistingof monofunctional monomers, difunctional monomers and mixtures thereof,a photoinitiator, a polyester resin and a polycarboxylic acid.
 28. Themethod of claim 27, wherein the multifunctional oligomer comprises about10% to about 80% by weight of the composition, the monomer comprisesabout 25% to about 75% by weight of the composition, the photoinitiatorcomprises 0.001% to about 6% by weight of the composition, the polyesterresin comprises about 1% to about 20% by weight of the composition, andthe polycarboxylic acid comprises about 0.01% to about 10% by weight ofthe composition.
 29. The method of claim 26, wherein the composition issubstantially free of organic solvent.
 30. The method of claim 26,wherein the composition comprises no more than about 5% by weight of anorganic solvent.
 31. The method of claim 30, wherein the compositioncomprises no more than about 1% by weight of an organic solvent.
 32. Themethod of claim 28, wherein the composition comprises a supplementaladhesion promoter, and wherein the multifunctional oligomer comprisesabout 15% to about 60% by weight of the composition, the monomercomprises about 30% to about 65% by weight of the composition, thephotoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 15% byweight of the composition, the polycarboxylic acid comprises about 0.01%to about 5% by weight of the composition, and the supplemental adhesionpromoter comprises about 0.1% to about 20% by weight of the composition.33. The method of claim 27, wherein the multifunctional oligomer is atrifunctional aliphatic polyester urethane acrylate oligomer and has amolecular weight of from about 1,200 to about 3,000.
 34. The method ofclaim 33, wherein the monomer is selected from the group consisting ofisobornyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate, andmixtures thereof.
 35. The method of claim 34, wherein the photoinitiatoris selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,1-hydroxy-cyclohexylphenylketone,2-hydroxy-2-methyl-1-phenyl-1-propanone, phosphine derivatives andmixtures thereof.
 36. The method of claim 32, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobomyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, and the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, and acrylic acrylate, and mixtures thereof. 37.The method of claim 32, wherein the multifunctional oligomer comprisesabout 20% to about 55% by weight of the composition, the monomercomprises about 30% to about 55% by weight of the composition, thephotoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 10% byweight of the composition, the polycarboxylic acid comprises about 0.01%to about 3% by weight of the composition, and the supplemental adhesionpromoter is selected from the group consisting of a phosphoric acidester, an acrylic, and acrylic acrylate, and mixtures thereof, andwherein the monomer comprises at least about 50% by weight of amonofunctional monomer.
 38. The method of claim 37, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobornyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, and the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof. 39.The method of claim 27 further comprising a colorant.
 40. The curablecoating composition of claim 39, wherein the colorant is a pigment, thecurable coating comprises a monofunctional monomer and a difunctionalmonomer, and wherein the weight ratio of the monofunctional monomer tothe difunctional monomer ranges from about 1:1 to about 5:1.
 41. Themethod of claim 39, wherein the multifunctional oligomer comprises about15% to about 60% by weight of the composition, the monomer comprisesabout 30% to about 65% by weight of the composition, the photoinitiatorcomprises 0.001% to about 6% by weight of the composition, the polyesterresin comprises about 1% to about 10% by weight of the composition, andthe polycarboxylic acid comprises about 0.01% to about 10% by weight ofthe composition.
 42. The method of claim 41, wherein the compositionfurther comprises an adhesion promoter, wherein the multifunctionaloligomer comprises a trifunctional aliphatic polyester urethane acrylateoligomer and has a molecular weight from about 1,200 to about 3,000, themonomer is selected from the group consisting of isobornyl acrylate,isodecyl acrylate, 1,6 hexanediol diacrylate and mixtures thereof, thephotoinitiator is selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof, andthe colorant is a pigment.
 43. The method of claim 42, wherein themultifunctional oligomer comprises about 40%l to about 60% by weight ofthe composition, the monomer comprises about 35% to about 55% by weightof the composition, the photoinitiator comprises 0.001% to about 4% byweight of the composition, the polyester resin comprises about 1% toabout 10% by weight of the composition, the polycarboxylic acidcomprises about 0.01% to about 5% by weight of the composition, thesupplemental adhesion promoter comprises about 0.1% to about 3% byweight of the composition, and the pigment comprises about 0.1% to about10% by weight of the composition, and wherein the monomer comprises atleast about 50% by weight of a monofunctional monomer.
 44. The method ofclaim 27, wherein the coating composition further comprises an aestheticagent.
 45. The method of claim 44, wherein the curable coating comprisesa monofunctional monomer and a difunctional monomer, and wherein theweight ratio of the monofunctional monomer to the difunctional monomerranges from about 20:1 to about 5:1.
 46. The method of claim 44, whereinthe multifunctional oligomer comprises about 15% to about 45% by weightof the composition, the monomer comprises about 30% to about 70% byweight of the composition, the photoinitiator comprises 0.001% to about6% by weight of the composition, the polyester resin comprises about 1%to about 10% by weight of the composition, the polycarboxylic acidcomprises about 0.01% to about 5% by weight of the composition, and theaesthetic agent comprises about 0.1% to about 30% by weight of thecomposition.
 47. The method of claim 46, wherein the coating compositionfurther comprises a supplemental adhesion promoter, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobornyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an an acrylic, an acrylic acrylate, and mixtures thereof,and the aesthetic agent is selected from the group consisting of silicasand, quartz grit. silica, talc and mixtures thereof.
 48. The method ofclaim 47, wherein the multifunctional oligomer comprises about 20% toabout 30% by weight of the composition, the monomer comprises about 50%to about 60% by weight of the composition, the photoinitiator comprises0.001% to about 4% by weight of the composition, the polyester resincomprises about 1% to about 10% by weight of the composition, thepolycarboxylic acid comprises about 0.01% to about 3% by weight of thecomposition, the supplemental adhesion promoter comprises about 0.1% toabout 3% by weight of the composition, and the aesthetic agent comprisesabout 0.1% to about 20% by weight of the composition.
 49. The method ofclaim 44, wherein the coating composition further comprises a colorant.50. The method of claim 49, wherein the multifunctional oligomercomprises about 15% to about 45% by weight of the composition, themonomer comprises about 30% to about 60% by weight of the composition,the photoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 10% byweight of the composition, the polycarboxylic acid comprises about 0.01%to about 5% by weight of the composition, the aesthetic agent comprisesabout 0.1% to about 30% by weight of the composition, and the colorantcomprises about 0.1% to about 15% by weight of the composition.
 51. Themethod of claim 50, wherein the coating composition further comprises asupplemental adhesion promoter, wherein the multifunctional oligomercomprises a trifunctional aliphatic polyester urethane acrylate oligomerand has a molecular weight from about 1,200 to about 3,000, the monomeris selected from the group consisting of isobornyl acrylate, isodecylacrylate, 1,6 hexanediol diacrylate and mixtures thereof, thephotoinitiator is selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof, theaesthetic agent is selected from the group consisting of silica sand,quartz grit, silica, talc, and mixtures thereof, and the colorantcomprises a pigment.
 52. The method of claim 51, wherein themultifunctional oligomer comprises about 20% to about 30% by weight ofthe composition, the monomer comprises about 30% to about 45% by weightof the composition, the photoinitiator comprises 0.001% to about 6% byweight of the composition, the polyester resin comprises about 1% toabout 10% by weight of the composition, the polycarboxylic acidcomprises about 0.01% to about 3% by weight of the composition, thesupplemental adhesion promoter comprises about 0.1% to about 20% byweight of the composition, the aesthetic agent comprises about 0.1% toabout 20% by weight of the composition, and the pigment comprises about0.1% to about 5% of the composition.
 53. The method of claim 27, whereinthe composite substrate is not primed prior to the application of thecurable coating onto the substrate.
 54. The method of claim 27, whereinthe curable coating is cured using UV radiation.
 55. The method of claim54, wherein the coated substrate is cured using at least two differentUV wavelengths.
 56. The method of claim 27, wherein the compositesubstrate is a plastic composite substrate.
 57. The method of claim 27,wherein the composite substrate is a cementitious composite substrate.58. The method of claim 27, wherein the composite substrate is a ceramiccomposite substrate.
 59. The method of claim 27, wherein the compositesubstrate is a PVC composite substrate.
 60. The method of claim 27,wherein the composite substrate is engineered wood.
 61. A coatedcomposite substrate comprising a composite substrate and a cured coatingon the surface of the substrate, wherein the cured coating is formed bycuring a curable coating composition comprising a multifunctionaloligomer, a monomer selected from the group consisting of monofunctionalmonomers, difunctional monomers and mixtures thereof, a photoinitiator,a polyester resin and a polycarboxylic acid.
 62. The coated compositesubstrate of claim 61, wherein the multifunctional oligomer comprisesabout 10% to about 80% by weight of the composition, the monomercomprises about 25% to about 75% by weight of the composition, thephotoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 20% byweight of the composition, and the polycarboxylic acid comprises about0.01% to about 10% by weight of the composition.
 63. The coatedcomposite substrate of claim 61, wherein the composition issubstantially free of solvent.
 64. The coated composite substrate ofclaim 61, wherein the composition comprises no more than about 5% byweight of an organic solvent.
 65. The coated composite substrate ofclaim 64, wherein the composition comprises no more than about 1% byweight of an organic solvent.
 66. The coated composite substrate ofclaim 63, wherein the coating composition further comprises asupplemental adhesion promoter, the multifunctional oligomer comprisesabout 25% to about 60% by weight of the composition, the monomercomprises about 30% to about 65% by weight of the composition, thephotoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 15% byweight of the composition, the polycarboxylic acid comprises about 0.01%to about 5% by weight of the composition, and the supplemental adhesionpromoter comprises about 0.1% to about 5% by weight of the composition.67. The coated composite substrate of claim 61, wherein themultifunctional oligomer is a trifunctional aliphatic polyester urethaneacrylate oligomer and has a molecular weight of from about 1,200 toabout 3,000.
 68. The coated composite substrate of claim 67, wherein themonomer is selected from the group consisting of isobornyl acrylate,isodecyl acrylate, 1,6 hexanediol diacrylate, and mixtures thereof. 69.The coated composite substrate of claim 68, wherein the photoinitiatoris selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives, and mixturesthereof.
 70. The coated composite substrate of claim 66, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobornyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, and the supplementaladhesion is selected from the group consisting of a phosphoric acidester, an acrylic, an acrylic acrylate and mixtures thereof.
 71. Thecoated composite substrate of claim 66, wherein the multifunctionaloligomer comprises about 20% to about 55% by weight of the composition,the monomer comprises about 30% to about 55% by weight of thecomposition, the photoinitiator comprises 0.001% to about 4% by weightof the composition, the polyester resin comprises about 1% to about 10%by weight of the composition, the polycarboxylic acid comprises about0.01% to about 5% by weight of the composition, and the supplementaladhesion promoter comprises about 0.1% to about 20% by weight of thecomposition, and wherein the monomer comprises at least about 50% byweight of a monofunctional monomer.
 72. The coated composite substrateof claim 71, wherein the multifunctional oligomer comprises atrifunctional aliphatic polyester urethane acrylate oligomer and has amolecular weight from about 1,200 to about 3,000, the monomer isselected from the group consisting of isobornyl acrylate, isodecylacrylate, 1,6 hexanediol diacrylate and mixtures thereof, thephotoinitiator is selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, and the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof. 73.The coated composite substrate of claim 61 further comprising acolorant.
 74. The coated composite substrate of claim 73, wherein thecolorant is a pigment, the curable coating comprises a monofunctionalmonomer and a difunctional monomer, and wherein the weight ratio of themonofunctional monomer to the difunctional monomer ranges from about 1:1to about 5:1.
 75. The coated composite substrate of claim 73, whereinthe multifunctional oligomer comprises about 15% to about 60% by weightof the composition, the monomer comprises about 30% to about 65% byweight of the composition, the photoinitiator comprises 0.001% to about6% by weight of the composition, the polyester resin comprises about 1%to about 10% by weight of the composition, and the polycarboxylic acidcomprises about 0.01% to about 5% by weight of the composition.
 76. Thecoated composite substrate of claim 75, wherein the coating compositionfurther comprises a supplemental adhesion promoter, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobomyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate and mixtures thereof, andthe colorant is a pigment.
 77. The coated composite substrate of claim76, wherein the multifunctional oligomer comprises about 40%l to about60% by weight of the composition, the monomer comprises about 35% toabout 55% by weight of the composition, the photoinitiator comprises0.001% to about 4% by weight of the composition, the polyester resincomprises about 1% to about 10% by weight of the composition, thepolycarboxylic acid comprises about 0.01% to about 3% by weight of thecomposition, the supplemental adhesion promoter comprises about 0.1% toabout 3% by weight of the composition, and the pigment comprises about0.1% to about 10% by weight of the composition, and wherein the monomercomprises at least about 50% by weight of a monofunctional monomer. 78.The coated composite substrate of claim 61, wherein the coatingcomposition further comprises an aesthetic agent.
 79. The coatedcomposite substrate of claim 78, wherein the curable coating comprises amonofunctional monomer and a difunctional monomer, and wherein theweight ratio of the monofunctional monomer to the difunctional monomerranges from about 20:1 to about 5:1.
 80. The coated composite substrateof claim 78, wherein the multifunctional oligomer comprises about 15% toabout 45% by weight of the composition, the monomer comprises about 30%to about 70% by weight of the composition, the photoinitiator comprises0.001% to about 6% by weight of the composition, the polyester resincomprises about 1% to about 10% by weight of the composition, thepolycarboxylic acid comprises about 0.01% to about 5% by weight of thecomposition, and the aesthetic agent comprises about 0.1% to about 30%by weight of the composition.
 81. The coated composite substrate ofclaim 80, wherein the coating composition further comprises apolycarboxylic acid and an adhesion promoter, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobornyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the supplemental adhesion promoter is selected from the groupconsisting of a phosphoric acid ester, an acrylic, an acrylic acrylate,and mixtures thereof, the polycarboxylic acid is unsaturated, and theaesthetic agent is chosen from the group consisting of silica sand,quartz grit, silica, talc, or mixtures thereof
 82. The coated compositesubstrate of claim 81, wherein the multifunctional oligomer comprisesabout 20% to about 30% by weight of the composition, the monomercomprises about 50% to about 60% by weight of the composition, thephotoinitiator comprises 0.001% to about 4% by weight of thecomposition, the polyester resin comprises about 1% to about 10% byweight of the composition, the polycarboxylic acid comprises about 0.01%to about 3% by weight of the composition, the supplemental adhesionpromoter comprises about 0.1% to about 3% by weight of the composition,and the aesthetic agent comprises about 0.1% to about 20% by weight ofthe composition.
 83. The coated composite substrate of claim 78, whereinthe coating composition further comprises a colorant.
 84. The coatedcomposite substrate of claim 83, wherein the multifunctional oligomercomprises about 15% to about 45% by weight of the composition, themonomer comprises about 30% to about 60% by weight of the composition,the photoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 10% byweight of the composition, the polycarboxylic acid comprises about 0.01%to about 5% by weight of the composition, the aesthetic agent comprisesabout 0.1% to about 30% by weight of the composition, and the colorantcomprises about 0.1% to about 15% by weight of the composition.
 85. Thecoated composite substrate of claim 84, wherein the coating compositionfurther comprises a supplemental adhesion promoter, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobomyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof, theaesthetic agent is selected from the group consisting of silica sand,quartz grit, silica, talc and mixtures thereof, and the colorantcomprises a pigment.
 86. The coated composite substrate of claim 85,wherein the multifunctional oligomer comprises about 20% to about 30% byweight of the composition, the monomer comprises about 30% to about 45%by weight of the composition, the photoinitiator comprises 0.001% toabout 6% by weight of the composition, the polyester resin comprisesabout 1% to about 10% by weight of the composition, the polycarboxylicacid comprises about 0.01% to about 3% by weight of the composition, thesupplemental adhesion promoter comprises about 0.1% to about 20% byweight of the composition, the aesthetic agent comprises about 0.1% toabout 20% by weight of the composition and the pigment comprises about0.1% to about 15% of the composition.
 87. The coated composite substrateof claim 61, wherein the substrate is not primed prior to theapplication of the curable coating.
 88. The coated composite substrateof claim 61, wherein the coated substrate is cured using UV radiation.89. The coated composite substrate of claim 88, wherein the coatedsubstrate is cured using at least two different UV wavelengths.
 90. Thecoated composite substrate of claim 61, wherein the composite substrateis a plastic composite substrate.
 91. The coated composite substrate ofclaim 61, wherein the composite substrate is a cementitious compositesubstrate.
 92. The coated composite substrate of claim 61, wherein thecomposite substrate is a ceramic composite substrate.
 93. The coatedcomposite substrate of claim 61, wherein the composite substrate is aPVC composite substrate.
 94. The coated composite substrate of claim 61,wherein the composite substrate is engineered wood.
 95. A method forproviding a plastic substrate with a cured coating comprising applying acurable coating composition onto a plastic substrate and curing thecoating composition, wherein the curable coating composition comprises amultifunctional oligomer, a monomer selected from the group consistingof monofunctional monomers, difunctional monomers and mixtures thereof,a photoinitiator, a polyester resin and a polycarboxylic acid.
 96. Themethod of claim 95, wherein the multifunctional oligomer comprises about10% to about 80% by weight of the composition, the monomer comprisesabout 25% to about 75% by weight of the composition, the photoinitiatorcomprises 0.001% to about 6% by weight of the composition, the polyesterresin comprises about 1% to about 20% by weight of the composition, andthe polycarboxylic acid comprises about 0.01% to about 10% by weight ofthe composition.
 97. The method of claim 95, wherein the compositioncomprises no more than about 1% by weight of an organic solvent.
 98. Themethod of claim 96, wherein the composition comprises a supplementaladhesion promoter, and wherein the multifunctional oligomer comprisesabout 15% to about 60% by weight of the composition, the monomercomprises about 30% to about 65% by weight of the composition, thephotoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 15% byweight of the composition, the polycarboxylic acid comprises about 0.01%to about 5% by weight of the composition, and the supplemental adhesionpromoter comprises about 0.1% to about 20% by weight of the composition.99. The method of claim 98, wherein the multifunctional oligomercomprises a trifunctional aliphatic polyester urethane acrylate oligomerand has a molecular weight from about 1,200 to about 3,000, the monomeris selected from the group consisting of isobornyl acrylate, isodecylacrylate, 1,6 hexanediol diacrylate and mixtures thereof, thephotoinitiator is selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, and the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, and acrylic acrylate, and mixtures thereof. 100.The method of claim 96 further comprising a colorant.
 101. The method ofclaim 100, wherein the composition further comprises an adhesionpromoter, wherein the multifunctional oligomer comprises a trifunctionalaliphatic polyester urethane acrylate oligomer and has a molecularweight from about 1,200 to about 3,000, the monomer is selected from thegroup consisting of isobornyl acrylate, isodecyl acrylate, 1,6hexanediol diacrylate and mixtures thereof, the photoinitiator isselected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof, andthe colorant is a pigment.
 102. The method of claim 96, wherein thecoating composition further comprises an aesthetic agent.
 103. Themethod of claim 96, wherein the composite substrate is not primed priorto the application of the curable coating onto the substrate.
 104. Themethod of claim 96, wherein the curable coating is cured using UVradiation.
 105. The method of claim 104, wherein the coated substrate iscured using pulsed UV radiation.
 106. A coated plastic substratecomprising a plastic substrate and a cured coating on the surface of thesubstrate, wherein the cured coating is formed by curing a curablecoating composition comprising a multifunctional oligomer, a monomerselected from the group consisting of monofunctional monomers,difunctional monomers and mixtures thereof, a photoinitiator, apolyester resin and a polycarboxylic acid.
 107. The coated plasticsubstrate of claim 106, wherein the multifunctional oligomer comprisesabout 10% to about 80% by weight of the composition, the monomercomprises about 25% to about 75% by weight of the composition, thephotoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 20% byweight of the composition, and the polycarboxylic acid comprises about0.01% to about 10% by weight of the composition.
 108. The coated plasticsubstrate of claim 106, wherein the composition comprises no more thanabout 1% by weight of an organic solvent.
 109. The coated plasticsubstrate of claim 107, wherein the composition comprises a supplementaladhesion promoter, and wherein the multifunctional oligomer comprisesabout 15% to about 60% by weight of the composition, the monomercomprises about 30% to about 65% by weight of the composition, thephotoinitiator comprises 0.001% to about 6% by weight of thecomposition, the polyester resin comprises about 1% to about 15% byweight of the composition, the polycarboxylic acid comprises about 0.01%to about 5% by weight of the composition, and the supplemental adhesionpromoter comprises about 0.1% to about 20% by weight of the composition.110. The coated plastic substrate of claim 109, wherein themultifunctional oligomer comprises a trifunctional aliphatic polyesterurethane acrylate oligomer and has a molecular weight from about 1,200to about 3,000, the monomer is selected from the group consisting ofisobornyl acrylate, isodecyl acrylate, 1,6 hexanediol diacrylate andmixtures thereof, the photoinitiator is selected from the groupconsisting of phenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, and the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, and acrylic acrylate, and mixtures thereof 111.The coated plastic substrate of claim 106 further comprising a colorant.112. The coated plastic substrate of claim 111, wherein the compositionfurther comprises an adhesion promoter, wherein the multifunctionaloligomer comprises a trifunctional aliphatic polyester urethane acrylateoligomer and has a molecular weight from about 1,200 to about 3,000, themonomer is selected from the group consisting of isobornyl acrylate,isodecyl acrylate, 1,6 hexanediol diacrylate and mixtures thereof, thephotoinitiator is selected from the group consisting ofphenylbis(2,4,6-trimethylbenzoyl)-phosphine oxide,2-hydroxy-2-methyl-1-phenyl-1-propanone,1-hydroxy-cyclohexylphenylketone, phosphine derivatives and mixturesthereof, the polycarboxylic acid is unsaturated, the supplementaladhesion promoter is selected from the group consisting of a phosphoricacid ester, an acrylic, an acrylic acrylate, and mixtures thereof, andthe colorant is a pigment.
 113. The coated plastic substrate of claim106, wherein the coating composition further comprises an aestheticagent.
 114. The coated plastic substrate of claim 106, wherein thecomposite substrate is not primed prior to the application of thecurable coating onto the substrate.
 115. The coated plastic substrate ofclaim 106, wherein the curable coating is cured using UV radiation. 116.The coated plastic substrate of claim 115, wherein the coated substrateis cured using pulsed UV radiation.